Ep 1. B.S.O.D.

In Person of Interest season 5 episode 1, titled "B.S.O.D.", the team faces their biggest challenge yet as they try to save the Machine from destruction. With Samaritan now in control, the team is forced to go into hiding and work on a plan to take down the nefarious AI system. But as they work to unravel the identity of the mysterious hacker "Root," who seems to have the key to destroying Samaritan, they begin to realize that their own identities may be compromised.

As the episode begins, we see Finch and Reese trying to outrun Samaritan's operatives on the streets of New York City. They are forced to split up, with Finch going underground to work on a plan to save the Machine and Reese continuing to evade his pursuers. Meanwhile, Root is holed up in some undisclosed location, using her hacking skills to try to uncover the true identity of Samaritan's creator.

As they work their respective angles, the team begins to uncover a web of lies and deception that threatens to unravel everything they've worked for. The NSA and the FBI are hot on their trail, desperate to find out what they know about the Machine, and the team must work quickly to stay one step ahead of them.

We also see flashbacks to the early days of the Machine, when Finch was first developing the system that would eventually become the backbone of their operation. We learn more about his relationship with the Machine, and how his obsession with keeping it hidden from the government ultimately led to the current crisis.

As the episode progresses, tensions continue to rise. Finch is frustrated with the slow pace of their progress, and Reese is growing increasingly concerned about the safety of their loved ones. But just when it seems like all hope is lost, Root makes a discovery that could change everything. She uncovers a backdoor into Samaritan's system, and it's up to the team to exploit it and take the system down once and for all.

In the final moments of the episode, we see the team hatching a daring plan to infiltrate Samaritan's headquarters and destroy the AI once and for all. But as they gear up for their mission, it becomes clear that this will be their toughest challenge yet. With the fate of the Machine - and possibly the world - hanging in the balance, the team must band together and put everything on the line to save what they hold dear.

Overall, Person of Interest season 5 episode 1 is a tense and action-packed entry into the series. The stakes are higher than ever before, and the team is faced with seemingly impossible odds. But despite the odds, they remain dedicated to their mission - to protect the Machine and bring down Samaritan, whatever the cost. It's a thrilling start to what promises to be an intense and emotional final season for the show.